wartsila fp

8/8/2019 Wartsila FP

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WÄRTSILÄ FIXED PITCHPROPELLER SOLUTIONS



PROPULSIONSOLUTIONS WITHFIXED PITCHPROPELLERSEach ship’s hull has its own characteristics.

For the vessel to achieve the highest possible

overall eciency, the propeller must beperectly matched with the engine and hull.

The Wärtsilä xed pitch propeller is the

choice when optimum eciency, reliability

and robustness are required.

Wärtsilä is able to solve all your

needs with regard to xed pitch propeller

installations:

Total system solutions supplied•

Easy assembly and maintenance•

Durable construction•

Optimum eciency through tailor-made•

design

Worldwide service and maintenance.•

All WÄRTSILÄ® propellers are custom designed

and made or each specic application.

The propellers vary in diameter rom 1 to

12 metres, and can weigh rom hundreds o

kilos to 140 tonnes.

Given the complex geometry o modern

propellers, the casting process is monitored

rom start to nish to ensure the highest

quality.Wärtsilä has produced some 9000 FP

propellers to date, or ocean-going vessels,

such as containerships, tankers, bulk carriers,

and dry cargo vessels.

The tailor-made design and use o the

latest available technology that are eatures

o Wärtsilä FP propellers or all ship types,

guarantee maximum eciency with minimum

noise and vibration levels. They are also easy

to repair.

Wärtsilä’s patented Cunial® material

provides excellent cast ing, machining, and

atigue strength properties.Wärtsilä FP propellers can be produced

with any required blade number and size,

rom 3.5 m upwards. For the smaller sizes,

as mostly used in ships or coastal and inland

WÄRTSILÄ FIXED PITCH PROPELLERS

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The mechanical properties o Cunial:

Mass density 7650 kg/m3

E-modulus (at 20° C) 121000 N/mm2

Poisson’s ratio 0.33

Yield stress min. 250 N/mm 2 *

Tensile strength min. 650 N/mm2

Elongation (longitudinal) min. 18%

Coecient o thermal expansion(rom 20 to 100°C)

16 ·10-6 K-1

*At request the yield stress o the material can be increased up to 270 N/mm2

waterways, our Wärtsilä Coastal and Inland

Propulsion Systems (CIPS) product group is

available to serve this market, which also

includes luxury motor yachts.

THE PRODUCTIONPROCESS

O the more than 25 dierent bronze alloysdeveloped by Wärtsilä or marine propellers,

Cunial bronze is the most used and thereore

the best-known material. Cunial bronze, which

stands or an alloy composed o copper, nickel

and aluminium, has unparalleled durability

and reliability. The high quality o this alloy is

the result o years o research. Monitoring is

carried out throughout the melting process to

check that the various elements are present in

the correct composition.

Having complete control over the production

process provides us with valuable inormation,

such as the atigue strength in seawater. Thisinormation in turn allows our hydrodynamic

design team to design the propellers according

to eciency limits, thus minimizing propeller

weight.

Casting the orm o a marine propeller is an

extremely complex procedure. To predict

the casting process, we use solidication

simulation sotware or dicult propeller

geometries. Accurate control o the process

allows us to use a minimum casting allowance.

Today, Wärtsilä FP propellers are

increasingly being worked mechanically

with the aid o grinding robots. However, theexpertise and eye or detail o the nisher is

still critical to give the propeller that essential

nishing touch.

The production process o fxed pitch propellers.

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DESIGN PHILOSOPHYThe main targets when designing an FP

propeller are:

Eciency (related to speed)•

Cavitation behaviour (related to noise)•

Pressure pulses on the hull (related to•

vibrations)

Meeting the strength requirements.•

Wärtsilä FP propellers meet these demands,

and provide a wide variation in speed and

power densities or any type o ship. Our

design experience covers a range o vessel

applications, including high-powered ast

containerships, tankers, bulk carriers and

cruise liners.We have extensive hydrodynamic

knowledge and have developed design

tools based upon years o experience with

calculations, model test results, and ull-

scale measurements. Our research and

development eorts are dedicated towards

continuous improvement in the hydrodynamic

design o our propellers. To achieve this goal,

we co-operate with research institutes and

universities in joint research projects. Our aimis to improve our knowledge and ull scale

experience, and to improve our design and

analysis methods, including Computational

Fluid Dynamics (CFD).

PRODUCT PORTFOLIOWärtsilä is able to supply xed pitch propellers

with a maximum nished weight o over

140 tonnes. We also supply a wide array opropulsion equipment, such as shatlines,

shatline accessories, and rudders.

We produce our monobloc xed pitch

propellers as standard with a keyless bore.

This allows the propeller to be hydraulically

press-tted onto the propeller shat, a method

that oers two advantages. First, it avoids

the stress concentrations that develop when

installing the propeller with keys and keyways.

Furthermore, hydraulic mounting anddismounting is a relatively simple installation

procedure. Keyed propellers can also be

supplied on request.

FIXED PITCH PROPELLER (MONOBLOC)

Wärtsilä can supply xed pitch propellers with

any number o blades. The most common are

4-, 5- and 6-bladed propellers, but we have

also supplied propellers with up to 9 blades.The maximum propeller diameter supplied

so ar has been 11.64 m, and the heaviest

propeller has a nished weight o over

100 tonnes.

BUILT-UP PROPELLERS

Our standard built-up propellers are

mounted to the fange o the tail shat

and the blades are de-mountable, even

underwater. The hub is designed orstrength and robustness with the minimum

number o parts. The blades on the hub are

slightly adjustable.

FP propeller FEM mesh.

Built-up propeller hub.

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The main reasons or applying Wärtsilä built-

up propellers are:

Regular occurrence o blade damage by•

collision with ice or other objects

Easy transport in case o damage•

The possibility to slightly adjust the pitch•

according to sailing conditions, or ouling

o the hull.

We supply built-up propellers with a

minimum o 3 and a maximum o 6 blades,

or hub diameters ranging rom 600 mm to

2945 mm.

SHAFTLINE

Each ship’s shatline has its own design andrequirements. The propeller shat installation

has a proven basic design, which enables

easy installation in the ship:

Hydraulic toolsets•

Hydraulic nut•

Hydraulic ring•

Propeller and intermediate shats•

Hydraulic coupling fange•

Hydraulic sleeve coupling.•

SHAFTLINE ACCESSORIES

Sterntubes with or without bearings•

Seals and bearings•

Thrust bearings•

Torque measurement device•

Turning device•

Shat grounding device•

Shat locking device•

Shat brake.•

NOZZLES

The advantage o using a nozzle is in the

additional amount o thrust it develops. Various

types o nozzles, such as the 19A, 37 and

the LIPS HR high-eciency nozzle, can besupplied.

CONSULTANCY

On request we also assist in questions

regarding propeller and shatline design. In

the case o damaged propellers, or instance,

we are oten contacted or a second opinion

regarding propeller perormance, propeller

strength and material quality.

Our laboratory and metallurgical teamsare perectly equipped to answer all questions

related to material quality, ailure cause, and

repair possibilities.

FP propeller in hold o vessel during transport.

Full scale cavitation observation.

Bearing.

Seal.

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Over the years, shipowners and yards have

oten approached us or modernization and

replacement solutions or xed pitch propellers.

The main reasons or replacement are:The propeller has too much damage and•

cannot be repaired

Upgrading o the propeller design to•

modern standards

Improved eciency•

Lower propeller induced pressure pulses•

Change in mission prole•

Poor initial design.•

IMPROVING PROPELLER DESIGNWärtsilä has, in close co-operation with model

test institutes and universities, conducted

considerable research into improving propeller

design. As a result, the new techniques we

have developed enable us to design propellers

with higher eciency without increasing the

onboard levels o vibration and noise. This

results immediately in lower uel consumption.In general, the ollowing our options are

available or increasing eciency through

a new propeller design, assuming that the

geometry o the new propeller lies within the

geometry o the old propeller:

Reduce the blade area•

Change the blade contour•

Modiy the radial pitch distribution•

Apply the Wärtsilä tip-rake concept.•

REDUCING THE BLADE AREA

Reduction o the blade area may be possible

in cases where the calculated power density

o the propeller is relatively low compared to

Wärtsilä standards. Reducing the blade area

o an FP propeller, and optimizing the power

density to an acceptable Wärtsilä value, can

increase eciency by more than 3%.

CHANGING THE BLADE CONTOUR

When it is not possible or desirable to reduce

the blade area, changing the blade contour

is an alternative means o increasing the

eciency o the FP propeller. Recent projects

show that eciency improvements o 3-4%

can be achieved.

MODIFYING THE RADIAL PITCHDISTRIBUTION

In past designs, it was usual to apply some

kind o constant radial pitch distribution with

a constant load at all radii. However, this

REPLACEMENT OF FIXED PITCH PROPELLERS

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distribution can lead to intensive tip and hub

vortex cavitation, which may damage the

rudder and generate high-pressure pulses.

For this reason, modern FP propeller designavours a variable pitch distribution with better

cavitation behaviour and low pressure pulses.

However, i the pressure pulses are kept at the

same level as with the old design, reduction o

the blade area is possible and eciency will

increase.

APPLYING THE TIP-RAKE CONCEPT

The tip-rake concept can be applied to achieve

better eciency, resulting in uel savingsand/or higher ship speed. Relative eciency

improvements o 2-4 % compared to normal

propellers have thus ar been measured.

Tip-rake also leads to lower pressure pulse

levels and a quieter propeller, and thereore

more comort or the crew. When considering

replacement or modernization o the existing

propeller, it is worth investigat ing to whatextent a new, state-o-the-art propeller design

could reduce uel consumption and/or pressure

pulses.

WORLDWIDE SERVICE AND MAINTENANCEWe oer a worldwide service network thatensures reliable and ecient support,

and the quickest possible solution to

any propulsion problem, during the ull

operational lietime o the vessel.

Our service activities include:

Retrots and upgrades•

Metallurgical repairs•

Modications to heavy running propellers•

Underwater services and survey•

Original LIPS spare parts•

Personnel training programmes•

Helpdesk •

Worldwide eld service•

In-house overhaul/repair.•

Blade contour.

Radial pitch distribution.

The tip-rake concept.

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WÄRTSILÄ® is a registered trademark. Copyright © 2007 Wärtsilä Corporation.

1 2 . 2

0 0 7 / B o c k ´ s O f c e / L i t o s e t

Wärtsilä enhances the business of its customers by providing them

with complete lifecycle power solutions. When creating better and

environmentally compatible technologies, Wärtsilä focuses on the

marine and energy markets with products and solutions as well as

services. Through innovative products and services, Wärtsilä sets out

to be the most valued business partner of all its customers. This is

achieved by the dedication of more than 15,000 professionals manning

150 Wärtsilä locations in 70 countries around the world. Wärtsilä is

listed on The Nordic Exchange in Helsinki, Finland.

wartsila fp

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